Deck Board Calculator

Calculate deck boards needed from deck size, board width, spacing, and waste. Outputs board counts, linear feet, and board feet.

Inputs

Tip: Composite decking often uses 1/8 in spacing; wet-treated boards can use tighter gaps.

Results

Boards needed
29
Boards across: 26
Totals
464 ft
212.67 board ft (1 in thick)

Assumptions

  • Boards run parallel to the deck length.
  • Spacing is the gap between boards.
  • Board feet assume 1-inch thickness.
  • Waste applies to total board count.

Example

A 16 ft × 12 ft deck using 5.5 in boards, 0.125 in spacing, and 10% waste needs about 29 boards, or 464 linear feet.

FAQ

How much spacing between deck boards?

Most decks use 1/8 in to 1/4 in gaps depending on board type and moisture content.

What is a standard deck board width?

Common decking is sold as 5/4 or 2x6 boards with a typical actual width around 5.5 in.

How much waste should I add?

Plan on 5–10% waste for cuts, defects, and layout changes, and increase for diagonal patterns.